General Description. This Core facility is the "work horse" of this Center and is organized to provide technical expertise, equipment and personnel to Liver Center Investigators who wish to work with: a) Isolated cell preparations including: hepatocytes, cholangiocytes, endothelial cells, stellate cells, portal fibroblasts and hepatic lymphocytes, primarily from rat and mouse. Recently human hepatocytes have also been obtained, b) Cell culture facilities for short and long term cultures and cell lines, c) Isolated liver perfusion preparations for studies utilizing the whole organ, d) Gene expression using Quantitative real time PCR machine and Phosphor-imaging equipment or e) Altering gene expression in these cells and tissues using siRNA transfection and adenovirus infection technologies. By centralizing these procedures in a Core facility, investigators are assured of a high degree of quality control and preparations can often be used simultaneously by more then one investigator, f) Services a-c are also established at the Center's satellite facility at the Mt Desert Island Biological Laboratory for use of alternative models in marine species, primarily the small skate, Raja erinacea.